Human and animal blood comprises many proteins and enzymes, which possess e.g. therapeutic properties. Some of these proteins may be found in the red blood cells whereas others are found in solution in plasma or serum. Such proteins are the target for large-scale and specific isolation with the aim of purifying and standardising the proteins for use as human therapeutic agents. Examples of prominent blood proteins that are isolated for therapeutic use: albumin, immunoglobulin G, Factor IX, Factor VIII and alpha-1-proteinase inhibitor. Some of these proteins are produced in the scale of several thousand kg per year (albumin and IgG) while others are produced only in the gram to kilogram per year scale. However, on a worldwide basis many million liters of blood per year are processed for the purpose of isolating these proteins.
Blood, blood plasma and blood serum are extremely complicated protein containing solutions that comprise many other types of compounds other than the protein(s) or enzyme(s) of interest. The isolation of specific target molecules from this type of sample requires sophisticated and often multi-step purification procedures.
One common problem with the current production methods of especially immunoglobulin G is the substantial loss of immunoglobulin G during the purification process, estimated to be at least 30% to 35% of the total IgG content of the starting material. One challenge is to maintain the quality of viral inactivation and lack of impurities which can cause adverse reactions, while enlarging the yield of IgG. At the current production levels of IgG, what may be considered small increases in the yield are in fact highly significant. Even a 2% increase in efficiency would generate a remarkable increase in yield and productivity.
As such, a need exists for improved and more efficient methods for manufacturing IgG products.